I assume that the comparison occurs on the same computer. Otherwise check the same fonts are available on both. Don’t rely on what you see on screen. Look at the font menu in the toolbar. If font name is italics, the font does not exist on the computer and is substituted.
There are many design differences between ODF (Writer) and .doc(x) formats.
One of these is the definition of the page printable area.
In Word, margins define the “discourse” area and page decoration (header and footer) is taken from the margins leaving the discourse area unchanged.
in Writer, margins define an absolutely no-print area. The inter-margin area is shared between discourse, footer and header.
The correspondence between these paradigms is a matter of simple arithmetic. This is why the page setup reports different settings in Writer than in Word (or vice versa).
Another cause of discrepancy is manual formatting. Word has many shortcomings in its abstract formatting model which ends up in user adding manually directives for bold, italics, … These unnamed additions are a nightmare for the conversion process.
Word only manages paragraph styling where Writer offers paragraph, character, page, frame and list styling resulting in more robust (and paradoxically easier for the user once the notion is understood) formatting.
If, in addition, you don’t use the styling services in Word (aka. the stylesheet) and vertical space your text with empty paragraphs instead of tuning the spacing properties of paragraph styles, you quite systematically lose your page synchronisation.
Also, table “geometry” are not well converted between both suites.
To summarize, conversion gives acceptable results if the original document is consistently styled, is relatively simple (few tables and absolutely no tables nested inside tables) and does not use advanced features. This is the case for 99% of common documents but for the first argument (styling).
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